Water and chemicals are used to dye and finish cotton clothes, and polyesters and nylons aren't biodegradable.
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He bathes himself in all types of hair sprays, colognes, and polyesters, because, remember, this is the early '80s.
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But polyesters—the long-chain molecules of plastic that make up synthetic insulation—can take centuries to break down.
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Eilish's branded clothing will presumably adhere to H&M's sustainable guidelines, which call for petroleum-based polyesters to be recycled.
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The plant also manufactures products such as olefins, aromatics, ammonia, ethylene oxide, ethylene glycol, adhesives and unsaturated polyesters, the company's website showed.
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The major issue is that most of the fibers in these cheap garments are synthetics and polyesters, which are derived from oil and petroleum production.
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While the precise concoction of materials is a trade secret, Lavelle says his shirts include nylon, Lycra, spandex, cotton, and a variety of polyesters in their design.
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In tests carried out in a third party laboratory under two conditions (in landfill and marine environments), the PrimaLoft Bio fibers showed exponentially faster biodegradation than many comparable polyesters.
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Today, other mounting media, like polyesters and epoxies, are also used, and in order to create the smooth surface that is photographed, the sample is often polished rather than cut.
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However, the country's demand for ethylene, a building block for plastics and polyesters, will rise to 22 million tonnes by 29, from 20173 million tonnes in 22017, according to consultancy Globaldata.
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China, the world's top chemicals consumer, is allowing greater access by global majors and local independents to its massive chemicals market to feed plastics, coatings and adhesives to the fast-growing consumer electronics and automotive sectors, as well as polyesters for clothing.
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Polyesters are also used to make bottles, films, tarpaulin, sails (Dacron), canoes, liquid crystal displays, holograms, filters, dielectric film for capacitors, film insulation for wire and insulating tapes. Polyesters are widely used as a finish on high-quality wood products such as guitars, pianos and vehicle/yacht interiors. Thixotropic properties of spray-applicable polyesters make them ideal for use on open- grain timbers, as they can quickly fill wood grain, with a high-build film thickness per coat. Cured polyesters can be sanded and polished to a high- gloss, durable finish.
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Functioning as a diol, 2,5-BHF has applications in the manufacture of polyurethane foams and polyesters.
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They provide a more sustainable alternative to conventionally used plastics for mulch films. Providing the same benefits as detailed above, the problem of plastic accumulation in soils could be solved. Aliphatic polyesters and aliphatic-aromatic co-polyesters have shown to be promising groups of biodegradable polymers.
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Aliphatic polyesters are a diverse family of synthetic polymers of which are biocompatible, biodegradable, and non-toxic.Renard, E., V. Langlois, and P. Guérin. "Chemical Modifications of Bacterial Polyesters: From Stability to Controlled Degradation of Resulting Polymers." Corrosion Engineering, Science and Technology 42.4 (2007): 300-11. Web.
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Aliphatic polyesters can be assembled from lactones under very mild conditions, catalyzed anionically, cationically or metallorganically. A number of catalytic methods for the copolymerization of epoxides with cyclic anhydrides have also recently been shown to provide a wide array of functionalized polyesters, both saturated and unsaturated.
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Via the process called polycondensation, CHDM is a precursor to polyesters. It is one of the most important comonomers for production of polyethylene terephthalate (PET), or polyethylene terephthalic ester (PETE), from which plastic bottles are made. center Thermoplastic polyesters containing CHDM exhibit enhanced strength, clarity, and solvent resistance. The properties of the polyesters vary from the high melting crystalline poly(1,4-cyclohexylenedimethylene terephthalate), PCT, to the non-crystalline copolyesters derived from both ethylene glycol and CHDM.
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Black led the Polyesters to move into the next round for the first time in four conferences.
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Kelsey, Donald R., Scardion, Betty M., Grebowicz, Jamusz S., Chuah, Hoe H. High Impact, Amorphous Terephthalate Copolyesters of Rigid 2,2,4,4-Tetramethyl-1,3-cyclobutanediol with Flexible Diols. Macromolecules. Volume 33, 2000, pp. 5810-5818. The thermal and mechanical properties of CBDO-derived polyesters are often superior to conventional polyesters.
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The 1980 Tefilin Polyesters season was the first season of the franchise in the Philippine Basketball Association (PBA).
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Phenylacetaldehyde is used in the synthesis of polyesters where it serves as a rate-controlling additive during polymerization.
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One important class of condensation polymers are polyesters. They arise from the reaction of carboxylic acid and an alcohol. Examples include polyesters, e.g. polyethyleneterephthalate: :n HO-X-OH + n HO2C-Y-CO2H → [O-X-O2C-Y-C(O)]n \+ (3n-2) H2O poly-(R)-3-hydroxybutyrate (P3HB), a naturally-occurring polymer.
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These elastomers are either polyurethanes made by reacting PTMEG with diisocyanates, or polyesters made by reacting PTMEG with diacids or their derivatives. The polymer is also a starting material for thermoplastic polyurethane, thermoplastic polyesters, polyetheramide and cast polyurethane elastomers, used for instance in the wheels of roller skates and skateboards.
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You are an army of fools, wearing bright polyesters, riding camels, taking pictures of each other, haggard, dysenteric, thirsty.
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The 1981 Tefilin Polyesters season was the second and final season of the franchise in the Philippine Basketball Association (PBA).
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SEM picture of a bend in a high-surface area polyester fiber with a seven- lobed cross section Close-up of a polyester shirt Stretching polyester fabric Polyester is a category of polymers that contain the ester functional group in their main chain. As a specific material, it most commonly refers to a type called polyethylene terephthalate (PET). Polyesters include naturally occurring chemicals, such as in the cutin of plant cuticles, as well as synthetics such as polybutyrate. Natural polyesters and a few synthetic ones are biodegradable, but most synthetic polyesters are not.
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Cyclopentadecanolide is produced synthetically by ring expansion of cyclotetradecanone. Another synthesis route is the depolymerization of polyesters of 15-hydroxypentadecanoic acid.
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BPA is a precursor used in the production of a wide range of polymers including polycarbonates, polyesters, polysulfones, and polyester ketones.
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Unsaturated polyesters are thermosetting resins. They are generally copolymers prepared by polymerizing one or more diol with saturated and unsaturated dicarboxylic acids (maleic acid, fumaric acid...) or their anhydrides. The double bond of unsaturated polyesters reacts with a vinyl monomer, usually styrene, resulting in a 3-D cross-linked structure. This structure acts as a thermoset.
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Horst Köpnick, Manfred Schmidt, Wilhelm Brügging, Jörn Rüter, Walter Kaminsky "Polyesters" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2002. Although CBDO is most often used in polyesters, mixed copolycarbonates of CBDO and a series of bisphenols have also been synthesized. The differing reactivities of the cis and trans isomers have not been studied in depth.
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US20180022867A1Chen EY, Hong M, Tang X. Ring-opening polymerization methods and recyclable biorenewable polyesters. US20180118880A1 It is the cyclic dimer of GHB.
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Most expanding monomers are cationically polymerized, some anionically and very few even radically. Spiro orthoesters are forming, when homopolymerized, polyether polyesters. Reaction equation.Reaction equation.
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Ethylene glycol is primarily used in antifreeze formulations (50%) and as a raw material in the manufacture of polyesters such as polyethylene terephthalate (PET) (40%).
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PBT is closely related to other thermoplastic polyesters. Compared to PET (polyethylene terephthalate), PBT has slightly lower strength and rigidity, slightly better impact resistance, and a slightly lower glass transition temperature. PBT and PET are sensitive to hot water above (140 °F). PBT and PET need UV protection if used outdoors, and most grades of these polyesters are flammable, although additives can be used to improve both UV and flammability properties.
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Neopentyl glycol (IUPAC name: 2,2-dimethylpropane-1,3-diol) is an organic chemical compound. It is used in the synthesis of polyesters, paints, lubricants, and plasticizers. When used in the manufacture of polyesters, it enhances the stability of the product towards heat, light, and water. By esterification reaction with fatty or carboxylic acids, synthetic lubricating esters with reduced potential for oxidation or hydrolysis, compared to natural esters, can be produced.
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There are, however, few studies on the toxicology of CBDO for both long term and short term effects. CBDO has potential advantages relative to BPA as a building block for production of polyesters. CBDO is very stable thermally and mechanically. Polyesters prepared from CBDO are rigid materials, but the combination of CBDO with flexible diols results in materials with high impact resistance, low color, thermal stability, good photooxidative stability and transparency.
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Natural polyesters: Dufour's gland macrocyclic lactones form brood cell laminesters in Colletes bees. Science 204(4391), 415-17. earning them the nickname polyester bees.Eveleth, R. and D. Chachra.
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Compared to aliphatic polyesters, Nylon 6 has poor biodegradability. Strong interchain interactions from hydrogen bonds between molecular nylon chains is said to be the cause by some sources.
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Research on fire-retardant polymers was bolstered by the need for new types of synthetic polymers in World War II. The combination of a halogenated paraffin and antimony oxide was found to be successful as a fire retardant for canvas tenting. Synthesis of polymers, such as polyesters, with fire retardant monomers were also developed around this time.Robitschek, P.; Bean, C. T. Flame-Resistant Polyesters from Hexachlorocyclopentadiene. Ind. Eng. Chem. 1954, 46 (8), 1628-1632.
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Synthetic fibres in use for rope-making include polypropylene, nylon, polyesters (e.g. PET, LCP, Vectran), polyethylene (e.g. Dyneema and Spectra), Aramids (e.g. Twaron, Technora and Kevlar) and acrylics (e.g. Dralon).
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An oligoester is an ester oligomer chain containing a small number of repeating ester units (monomers). Oligoesters are short analogs of polymeric polyesters. An example is oligo-(R)-3-hydroxybutyrate.
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Polyester resin offers the following advantages: # Adequate resistance to water and variety of chemicals. # Adequate resistance to weathering and ageing. # Low cost. # Polyesters can withstand a temperature up to 80 °C.
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Cardo aromatic polyesters form a type of cardo polymer in which an ester group is incorporated in the backbone of the polymer chain and the ester groups are separated by an aromatic ring. A common form of cardo aromatic polyesters are ones in which bisphenol is incorporated into the monomers. These polymers can be synthesized via polycondensation. The hydroxyl groups coming off the bisphenol component of the monomers can react with acid chlorides, producing hydrochloric acid as a byproduct.
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Unsaturated polyesters are condensation polymers formed by the reaction of polyols (also known as polyhydric alcohols), organic compounds with multiple alcohol or hydroxy functional groups, with saturated or unsaturated dibasic acids. Typical polyols used are glycols such as ethylene glycol; acids used are phthalic acid, isophthalic acid and maleic acid. Water, a by-product of esterification reactions, is continuously removed, driving the reaction to completion. The use of unsaturated polyesters and additives such as styrene lowers the viscosity of the resin.
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After his coaching stint with Mariwasa, he became the athletic director of the University of the Philippines. However, he briefly returned to the bench via PBA expansion team Tefilin Polyesters from 1980 to 1981.
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Those that are more flammable can have their fire resistance drastically improved by treatment with fire-retardant chemicals. Inherently flame-retardant fabrics such as certain brand polyesters are commonly used for flame retardant curtain fabrics.
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Along with its good mechanical properties, its popularity is based on the non-toxic products that it becomes when it decomposes through hydrolytic degradation.Albertsson, Ann-Christine. Degradable Aliphatic Polyesters. Vol. 157. Berlin: Springer, 2002. Print.
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"Synthesis, Properties and Applications of Biodegradable Polymers Derived From Diols and Dicarboxylic Acids: From Polyesters to Poly(Ester Amide)S." International Journal of Molecular Sciences 15.5 (2014): 7064-7123. Academic Search Complete. Web. 20 Oct. 2014.
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Natural polyesters could have played a significant role in the origins of life. Long heterogeneous polyester chains and membraneless structures are known to easily form in a one-pot reaction without catalyst under simple prebiotic conditions.
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Antimony(III) acetate is the compound of antimony with the chemical formula of Sb(CH3CO2)3. It is a white powder, is moderately water-soluble, and is used as a catalyst in the production of polyesters.
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With hydrophilic fibres like cotton, wool, polyamide and polyacrylonitrile, sodium triphosphate removes soil more effectively than a surfactant alone. With hydrophobic fibres like polyesters and polyolefins, the effectiveness of the surfactant surpasses that of the builder.
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One of the most important and most studied groups of biodegradable polymers are polyesters. Polyesters can be synthesized in a number of ways including direct condensation of alcohols and acids, ring opening polymerizations (ROP), and metal-catalyzed polymerization reactions. A great disadvantage of the step-wise polymerization via condensation of an acid and an alcohol is the need to continuously remove water from this system in order to drive the equilibrium of the reaction forward. This can necessitate harsh reaction conditions and long reaction times, resulting in a wide dispersity.
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Strength, durability, cost, and stretch make polyester material the most widely used in fabric structures. Polyesters that are laminated or coated with PVC films are usually the least expensive option for longer-term fabrications. Laminates generally consist of vinyl films over woven or knitted polyester meshes (called scrims or substrates), while vinyl-coated polyesters usually have a high-count, high-tensile base fabric coated with a bondable substance that provides extra strength. Precontraint fabric is made by placing the polyester fabric under tension both before and during the coating process.
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Step-growth polymerization involves two monomers with bi- or multifunctionality to form polymer chains. Many polymers are synthesized via step-growth polymerization and include polyesters, polyamides, and polyurethanes. A sub class of step-growth polymerization is condensation polymerization.
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The properties of these polyesters also is affected by the cis/trans ratio of the CHDM monomer. CHDM reduces the degree of crystallinity of PET homopolymer, improving its processability. The copolymer tends to resist degradation, e.g. to acetaldehyde.
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It is also an urinary metabolite of tyrosine in rats. Polyesters have been prepared from phloretic acid. It is one of the products of flavonoid metabolism performed by the bacterium Clostridium orbiscindens, a resident of some human guts.
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The process leads to depolymerization. For this reason nylon products fail by fracturing when exposed to small amounts of acidic water. Polyesters are also susceptible to similar polymer degradation reactions. The problem is known as environmental stress cracking.
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PTC is widely exploited industrially.Marc Halpern "Phase- Transfer Catalysis" in Ullmann's Encyclopedia of Industrial Chemistry 2002, Wiley-VCH, Weinheim. Polyesters for example are prepared from acyl chlorides and bisphenol-A. Phosphothioate-based pesticides are generated by PTC- catalyzed alkylation of phosphothioates.
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Malonic acid is a precursor to specialty polyesters. It can be converted into 1,3-propanediol for use in polyesters and polymers and a projected market size of $621.2 million by 2021. It can also be a component in alkyd resins, which are used in a number of coatings applications for protecting against damage caused by UV light, oxidation, and corrosion. One application of malonic acid is in the coatings industry as a crosslinker for low-temperature cure powder coatings, which are becoming increasingly valuable for heat sensitive substrates and a desire to speed up the coatings process.
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Two molecules of lactic acid can be dehydrated to the lactone lactide. In the presence of catalysts lactide polymerize to either atactic or syndiotactic polylactide (PLA), which are biodegradable polyesters. PLA is an example of a plastic that is not derived from petrochemicals.
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2003, Scribner, New York. Several billion kilograms of polyesters are produced industrially annually, important products being polyethylene terephthalate, acrylate esters, and cellulose acetate. :Representative triglyceride found in a linseed oil, a triester (triglyceride) derived of linoleic acid, alpha-linolenic acid, and oleic acid.
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Neil McDonough’s father, Myles, founded FLEXcon in 1956. In those early years, the company focused on laminating vinyl and metallic polyesters for use in women's shoes and handbags. “You can never remain on a plane. You must either go up or down.” was Myles motto.
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The current economic method for the production of polyesters is direct esterification of dicarboxylic acids with diols. This condensation polymerization adds monomeric units to a chain. Individual chains react with one another through carboxyl and hydroxyl terminal groups. Finally, transesterification occurs within the chain.
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A wide variety of starting materials can be used to synthesize polyesters, and each monomer type endows the final polymer chain with different characteristics and properties. The ROP of cyclic dimeric glycolic or lactic acid forms α-hydroxy acids which then polymerize into poly-(α-esters). A variety of organometallic initiators can be used to start the polymerization of polyesters, including tin, zinc, and aluminum complexes. The most common is tin(II)octanoate and has been approved as a food additive by the U.S. FDA, but there are still concerns about using the tin catalysts in the synthesis of biodegradable polymers for biomedical uses.
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The most common RIM processable material is polyurethane (known generally as PU-RIM),. but others include polyureas, polyisocyanurates, polyesters, polyphenols, polyepoxides, and nylon 6. For polyurethane one component of the mixture is polyisocyanate and the other component is a blend of polyol, surfactant, catalyst, and blowing agent.
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They are less fire-resistant and can melt when ignited. Liquid crystalline polyesters are among the first industrially used liquid crystal polymers. They are used for their mechanical properties and heat-resistance. These traits are also important in their application as an abradable seal in jet engines.
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Pimelic acid is the organic compound with the formula HO2C(CH2)5CO2H. Derivatives of pimelic acid are involved in the biosynthesis of the amino acid called lysine. Pimelic acid is one unit longer than a related dicarboxylic acid, adipic acid, a precursor to many polyesters and polyamides.
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Like BPA, CBDO is a diol with a structure suitable for making polyesters. CBDO’s C4 ring is sufficiently rigid to prevent the two OH groups from forming cyclic structures. Unlike BPA, there is no current evidence of carcinogenic or toxic effects from CBDO-based consumer products.
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Roskydal are unsaturated polyesters which are contained in wood- and furniture coatings, conventionally curing or UV curing, coatings for musical instruments and interior fittings as well as putties for wood, commercial vehicle, automotive, stone- and marble applications. The first Roskydal types have been introduced by Bayer in the 1950s.
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Referred to as "chalk" in the plastic industry, calcium carbonate is derived from limestone and marble. It is used in many applications including PVC's and unsaturated polyesters. As much as 90% CaCO3 can be used to make a composite. These additions can improve molding productivity by decreasing cooling rate.
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Methanol is prepared from carbon monoxide or carbon dioxide. Bulk polymers derived from ethylene and propylene are often prepared via Ziegler-Natta catalysis. Polyesters, polyamides, and isocyanates are derived via acid-base catalysis. Most carbonylation processes require metal catalysts, examples include the Monsanto acetic acid process and hydroformylation.
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Polymerization of epoxides gives polyethers. For example ethylene oxide polymerizes to give polyethylene glycol, also known as polyethylene oxide. The reaction of an alcohol or a phenol with ethylene oxide, ethoxylation, is widely used to produce surfactants: :ROH + n C2H4O → R(OC2H4)nOH With anhydrides, epoxides give polyesters.
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Addressing principle #7 is a green route to 1,3-propanediol, which is traditionally generated from petrochemical precursors. It can be produced from renewable precursors via the bioseparation of 1,3-propanediol using a genetically modified strain of E. coli. This diol is used to make new polyesters for the manufacture of carpets.
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For example, body panels of an original Ford automobile were made of soy-based plastic. There are difficulties with using soy protein-based plastics due to their water sensitivity and relatively high cost. Therefore, producing blends of soy protein with some already-available biodegradable polyesters improves the water sensitivity and cost.
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Disperse Yellow 42, a popular dye for polyesters, is derived from 1,4-dichloro-2-nitrobenzene. 1,4-Dichloro-2-nitrobenzene is an organic compound with the formula C6H3Cl2NO2. One of several isomers of dichloronitrobenzene, it is a yellow solid that is insoluble in water. It is produced by nitration of 1,4-dichlorobenzene.
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1,5-Pentanediol is the organic compound with the formula HOCHCHCHCHCHOH. Like other diols, this viscous colourless liquid is used as plasticizer and also forms polyesters that are used as emulsifying agents and resin intermediates.Merck Index, 11th Edition, 7073. 1,5-Pentanediol is produced by hydrogenation of glutaric acid and its derivatives.
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1,8-Octanediol, also known as octamethylene glycol, is a diol with the molecular formula HO(CH)OH. 1,8-Octanediol is a white solid. It is produced by hydrogenation of esters of suberic acid. 1,8-Octanediol is used as a monomer in the synthesis of some polymers such as polyesters and polyurethanes.
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The first synthetic absorbable was based on polyvinyl alcohol in 1931. Polyesters were developed in the 1950s, and later the process of radiation sterilization was established for catgut and polyester. Polyglycolic acid was discovered in the 1960s and implemented in the 1970s. Today, most sutures are made of synthetic polymer fibers.
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Efforts have been made to develop modified dextran polymers. One of these has acetal modified hydroxyl groups. It is insoluble in water, but soluble in organic solvents. This allows it to be processed in the same manner as many polyesters, like poly(lactic-co-glycolic acid), through processes like solvent evaporation and emulsion.
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Most fabric structures are composed of actual fabric rather than meshes or films. Typically, the fabric is coated and laminated with synthetic materials for increased strength, durability, and environmental resistance. Among the most widely used materials are polyesters laminated or coated with polyvinyl chloride (PVC), and woven fiberglass coated with polytetrafluoroethylene (PTFE).
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This enzyme is required for production of dicarboxylic acids by industrial Candida yeast, which have nonfunctional beta oxidation pathways. They can thus produce relatively pure saturated and unsaturated dicarboxylic acids in high yield, which is not possible using chemical synthesis. The dicarboxylic acids are used to produce fragrances, polyamides, polyesters, adhesives, and antibiotics.
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Polyesters are also used in anchor bolt adhesives though epoxy based materials are also used. Many companies have and continue to introduce styrene free systems mainly due to odor issues. Most polyester resins are viscous, pale coloured liquids consisting of a solution of a polyester in a monomer which is usually styrene..
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Another way to form primitive compartments that may lead to the formation of a protocell is polyesters membraneless structures that have the ability to host biochemicals (proteins and RNA) and/or scaffold the assemblies of lipids around them. While these droplets are leaky towards genetic materials, this leakiness could have facilitated the progenote hypothesis.
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Translucent plastic film, which is usually of gray or a light khaki shade. Common types are 0.05, 0.07 and 0.10 mm thick. These films are also used in photocopying. The most commonly used materials are polyesters, and sometimes also PVC or polycarbonate; arguably, a proprietary eponym or genericized trademark for this is called Mylar.
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ECD studies of polyalkene glycols, polyamides, polyacrylates and polyesters are useful for understanding composition of polymer samples. It has become a powerful technique to analyze structural information about precursor ions during MS/MS for synthetic polymers. ECD's single bond cleavage tendency makes the interpretation of product ion scans simple and easy for polymer chemistry.
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In 1934, Carothers turned his attention to fibers again. Now the team substituted diamines for glycols to produce a type of polymer called a polyamide. These substances were much more stable than the polyesters formed by using the glycols. The ability of polyamides to form crystalline domains through hydrogen bonding gives them increased mechanical properties.
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DMT is used in the production of polyesters, including polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), and polybutylene terephthalate (PBT). It consists of benzene substituted with carboxymethyl groups (CO2CH3) at the 1 and 4 positions. Because DMT is volatile, it is an intermediate in some schemes for the recycling of PET, e.g. from plastic bottles.
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Plastics are usually classified by: the chemical structure of the polymer's backbone and side chains; some important groups in these classifications are: the acrylics, polyesters, silicones, polyurethanes, and halogenated plastics. Plastics can also be classified by: the chemical process used in their synthesis, such as: condensation, polyaddition, and cross-linking.Classification of Plastics . Dwb.unl.edu. Retrieved on 2011-07-01.
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UV susceptibility varies significantly between different polymers. Certain polycarbonates, polyesters and polyurethanes are highly susceptible, degrading via a Photo- Fries rearrangement. UV stabilisers absorb and dissipate the energy from UV rays as heat, typically by reversible intramolecular proton transfer. This reduces the absorption of UV rays by the polymer matrix and hence reduces the rate of weathering.
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Amongst others like Dupont and Corbion, the company Avantium claims to have developed a cost- effective route to produce FDCA and the derived polyesters. FDCA has also been applied in pharmacology. It was demonstrated that its diethyl ester had a strong anaesthetic action similar to cocaine. Dicalcium 2,5-furandicarboxylate was shown to inhibit the growth of Bacillus megatorium.
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The use of natural polymers has given way to artificially synthesized polymers such as polyanhydrides, polyesters, polyacrylic acids, poly(methyl methacrylates), and polyurethanes. Hydrophilic, amorphous, low-molecular- weight polymers containing heteroatoms (i.e., atoms other than carbon) have been found to degrade fastest. Scientists control the rate of drug delivery by varying these properties thus adjusting the rate of degradation.
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Green Chemistry, volume 19, issue 15, pages 3671-3678. Alessandro Pellis, Fergal P Byrne, James Sherwood, Marco Vastano, James W Comerford, Thomas J Farmer (2019) Safer bio-based solvents to replace toluene and tetrahydrofuran for the biocatalyzed synthesis of polyesters. Green Chemistry, volume 21, issue 7, pages 1686-1694. and as a reagent in chemical synthesis.
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Major chemical intermediates from the alkylation with ethylene is ethylbenzene, precursor to styrene. Styrene is used principally in polystyrene for packaging and insulation, as well as in styrene-butadiene rubber for tires and footwear. On a smaller scale, ethyltoluene, ethylanilines, 1,4-hexadiene, and aluminium alkyls. Products of these intermediates include polystyrene, unsaturated polyesters and ethylene-propylene terpolymers.
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Production of copious quantities of these acylsugars give a sticky feel to the plant tissue. In particular, this flower has shown to distract herbivorous insect pests against thrips damage. It is believed that acylsugars provide physical and/or chemical defense to the plant. Acylsugars are nonvolatile and viscous polyesters that consist of acyl chains on sucrose or glucose backbones.
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The material would then be painted white with water-soluble canvas paint. Leather buckles were used to bind the pad to the leg. These natural material pads were quite heavy. By contrast, modern day pads are now made from durable and ultra light synthetic materials such as PVC for the outer and polyesters for the lining.
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HMF itself has few applications. It can however be converted into other more useful compounds. Of these the most important is 2,5-furandicarboxylic acid, which has been proposed as a replacement for terephthalic acid in the production of polyesters. HMF can be converted to 2,5-dimethylfuran (DMF), a liquid that is a potential biofuel with a greater energy content than bioethanol.
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The insurers of the van driver admitted liability and the injured driver was compensated. Polycarbonate is susceptible to alkali hydrolysis, the reaction simply depolymerising the material. Polyesters are prone to degrade when treated with strong acids, and in all these cases, care must be taken to dry the raw materials for processing at high temperatures to prevent the problem occurring.
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Weil, E.D., Levchik, S.V. Flame retardants for plastics and textiles, p. 16. Hanser Publishers, Munich, Germany, 2009 Compounding with APP-based flame retardants in polypropylene is described in. Further applications are thermosets, where APP is used in unsaturated polyesters and gel coats (APP blends with synergists), epoxies and polyurethane castings (intumescent systems). APP is also applied to flame retard polyurethane foams.
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Styrene block copolymers (SBC), also called styrene copolymer adhesives and rubber-based adhesives, have good low-temperature flexibility, high elongation, and high heat resistance. They are frequently used in hot melt adhesive applications, where the composition retains tack even when solidified; however non-pressure- sensitive formulations are also used. High heat resistance, good low- temperature flexibility. Lower strength than polyesters.
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Open- and closed-cell metal foam can also be used as core materials. Laminates of glass or carbon fiber-reinforced thermoplastics or mainly thermoset polymers (unsaturated polyesters, epoxies...) are widely used as skin materials. Sheet metal is also used as skin material in some cases. The core is bonded to the skins with an adhesive or with metal components by brazing together.
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A dicarboxylic acid is an organic compound containing two carboxyl functional groups (−COOH). The general molecular formula for dicarboxylic acids can be written as HO2C−R−CO2H, where R can be aliphatic or aromatic. In general, dicarboxylic acids show similar chemical behavior and reactivity to monocarboxylic acids. Dicarboxylic acids are also used in the preparation of copolymers such as polyamides and polyesters.
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Wool and polyesters perform reasonably well for most weather conditions and provide some insulation while wet. Cotton/linen wicks moisture, good for hot/humid weather. Cotton, linen and down lose insulation when wet unless they are treated to be water-resistant. Natural fabrics, such as cotton, linen and wool have higher burn temperatures, and they char instead of melting when exposed to flame.
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Developing a host of new facilities in North America, Europe, and Asia, PGC has developed a competitive global supply chain and absorbed much of the original business functions of greater P&G.; Specializing in the production of glycerine, methyl esters, alcohols, amines, fatty alcohols, and sucrose polyesters like Sefose and Olean, PGC supplies a variety of oleochemicals to companies around the world.
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Vinyl ester resins made by addition reactions between an epoxy resin with acrylic acid derivatives, when diluted/dissolved in a vinyl functional monomer such as styrene, polymerise. The resulting thermosets are notable for their high adhesion, heat resistance and corrosion resistance. They are stronger than polyesters and more resistant to impact than epoxies.F.A. Cassis and R.C. Talbot in Handbook of Composites, ed.
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Later Davidoff (1886), and then Voländer (1894) prepared this same material by using different methods.This early work was pursued in the 1930s by Wallace Hume Carothers (E.I. du Pont de Nemours and Co.), with a more systematic study of succinic acid based polyesters. In that time the purpose of such study was to find a synthetic alternative to natural silk fiber.
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Carothers, by eliminating water in a continuous distillation process, obtained polymers with molar masses significantly higher than what was previously synthesized. Nevertheless, the properties of the final products did not show the expected qualities. Thus Carothers put more attention on polyamides and invented with his colleague Julian Hill Nylon 6,6. Later Flory (1946) proposed an improved synthesis of aliphatic polyesters with diacid chloride.
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Though light sweet oil has been used directly as a burner fuel, these lighter fragments form explosive vapors in fuel tanks, and thus are dangerous. The oil must be separated into various parts and refined before used in fuels and lubricants, and before some of the byproducts form materials such as plastics, detergents, solvents, elastomers, and fibers such as nylon and polyesters.
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In halogen- free system, zinc borate can be used together with alumina trihydrate, magnesium hydroxide, red phosphorus, or ammonium polyphosphate. During burning the plastics, a porous borate ceramics is formed that protects the underlying layers. In presence of silica, borosilicate glass can be formed at plastic burning temperatures. Zinc borate is used in polyvinyl chloride, polyolefins, polyamides, epoxy resins, polyesters, thermoplastic elastomers, rubbers, etc.
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Copolyester forms when modifications are made to polyesters, which are combinations of diacids and diols. For example, by introducing other diacids, such as isophthalic acid (IPA), or other diols, such as cyclohexane dimethanol (CHDM) to the polyester polyethylene terephthalate (PET), the material becomes a copolyester due to its comonomer content.Copolyester – A Versatile Choice for Medical Applications Thijs Jaarsma. 2004. Business Briefing: Medical Device Manufacturing & Technology.
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The properties of a photocured material, such as flexibility, adhesion, and chemical resistance are provided by the functionalized oligomers present in the photocurable composite. Oligomers are typically epoxides, urethanes, polyethers, or polyesters, each of which provide specific properties to the resulting material. Each of these oligomers are typically functionallized by an acrylate. An example shown below is an epoxy oligomer that has been functionalized by acrylic acid.
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Spinnaker, made of nylon because of its light weight and high strength. Nylon is used in spinnakers because of its light weight, high tensile strength, superior abrasion resistance and flexibility. However, it has a low modulus allowing too much stretch to be suitable for upwind sails. Nylon is more susceptible to UV and chemical degradation than polyesters and its physical properties can change due to moisture absorption.
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However, high-amylose starch has less processiblity because of its higher gelatinization temperature and higher melt viscosity. Starch-based bioplastics are often blended with biodegradable polyesters to produce starch/polylactic acid, starch/polycaprolactone or starch/Ecoflex (polybutylene adipate-co-terephthalate produced by BASF) blends. These blends are used for industrial applications and are also compostable. Other producers, such as Roquette, have developed other starch/polyolefin blends.
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Starch-based films (mostly used for packaging purposes) are made mainly from starch blended with thermoplastic polyesters to form biodegradable and compostable products. These films are seen specifically in consumer goods packaging of magazine wrappings and bubble films. In food packaging, these films are seen as bakery or fruit and vegetable bags. Composting bags with this films are used in selective collecting of organic waste.
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Polyhydroxyalkanoates are linear polyesters produced in nature by bacterial fermentation of sugar or lipids. They are produced by the bacteria to store carbon and energy. In industrial production, the polyester is extracted and purified from the bacteria by optimizing the conditions for the fermentation of sugar. More than 150 different monomers can be combined within this family to give materials with extremely different properties.
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Acetalated dextran is a biodegradable polymer based on dextran that has acetal modified hydroxyl groups. After synthesis, the hydrophilic polysaccharide dextran is rendered insoluble in water, but soluble in organic solvents. This allows it to be processed in the same manner as many polyesters, like poly(lactic-co-glycolic acid), through processes like solvent evaporation and emulsion. Acetalated dextran is structurally different from acetylated dextran.
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The knobs allowed a greater distance and allowed the automatic gimping around flowered patterns. The number of Leavers in use was dependent on the market and during periods of depression or cotton shortage many frames were broken up for their iron content. The use of Raschel machines, noted for being better for artificial fibres increased in the 1970s and, with fine polyesters, the two products have converged.
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Succinic acid is a precursor to some polyesters and a component of some alkyd resins. 1,4-Butanediol (BDO) can be synthesized using succinic acid as a precursor. The automotive and electronics industries heavily rely on BDO to produce connectors, insulators, wheel covers, gearshift knobs and reinforcing beams. Succinic acid also serves as the bases of certain biodegradable polymers, which are of interest in tissue engineering applications.
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Degradation can also be useful in biomedical settings. For example, a copolymer of polylactic acid and polyglycolic acid is employed in hydrolysable stitches that slowly degrade after they are applied to a wound. The susceptibility of a polymer to degradation depends on its structure. Epoxies and chains containing aromatic functionalities are especially susceptible to UV degradation while polyesters are susceptible to degradation by hydrolysis.
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P&G; Chemicals (PGC) is a division within Procter and Gamble that specializes in the production and distribution of oleochemicals throughout the world. With a line of products including glycerine, methyl esters, alcohols, fatty alcohols, and sucrose polyesters such as Sefose and Olean, PGC produces raw materials essential for many commonly used consumer products, and is a global supplier for some of the world’s largest chemical companies.
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A similar process (environmental stress cracking) occurs in polymers, when products are exposed to specific solvents or aggressive chemicals such as acids and alkalis. As with metals, attack is confined to specific polymers and particular chemicals. Thus polycarbonate is sensitive to attack by alkalis, but not by acids. On the other hand, polyesters are readily degraded by acids, and SCC is a likely failure mechanism.
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At the moment most of these poly(alkylene succinate)s are synthesized from petrochemical precursors. Nevertheless most of the producers are evaluating or developing bio-based succinic acid for the synthesis of these polyesters. In 2016, Showa Denko announced termination of the production and sale of Bionolle, citing delay in permeation of environmental regulations on plastic shopping bags and a fall in market prices of biodegradable plastics.
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Materials include nonwoven fibers (cotton, nylon, polyesters, glass), polymer films (polyethylene, polypropylene, poly (tetrafluoroethylene), polyvinyl chloride), ceramic and naturally occurring substances (rubber, asbestos, wood). Some separators employ polymeric materials with pores of less than 20 Å, generally too small for batteries. Both dry and wet processes are used for fabrication. Nonwovens consist of a manufactured sheet, web or mat of directionally or randomly oriented fibers.
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Some resins, such as polyesters, give off significant amounts of volatiles during cure. These will carry out through the vacuum ports and sometimes cause damage to the pump. The better vacuum pumps use oil reservoirs and oil recirculation, and these volatiles can quickly turn the oil into a revolting mush. They also attack the seals of vacuum valves and cause deposits to build up over time.
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Jeffrey Scott Moore was born in 1962 near Joliet, Illinois. He was awarded his B.S. in chemistry in 1984 and his Ph.D. in Materials Science and Engineering in 1989, both from the University of Illinois at Urbana–Champaign. At Illinois, he worked with Samuel I. Stupp on the molecular organization of polymers, and developed a new room temperature technique for the polyesterification of high molecular weight polyesters.
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Specialized gelcoats can be used to manufacture the moulds which in turn are used to manufacture components. These require very high levels of durability to overcome the mechanical and thermal stresses encountered during the curing and demoulding processes. Suitable resin chemistries for the manufacture of gelcoats vary, but the most commonly encountered are unsaturated polyesters or epoxies. Within each of these categories, the resin chemistries are further subdivided.
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PVC-based plumbing is selected for handling sewage because PVC resists biodegradation. Some packaging materials on the other hand are being developed that would degrade readily upon exposure to the environment. Examples of synthetic polymers that biodegrade quickly include polycaprolactone, other polyesters and aromatic-aliphatic esters, due to their ester bonds being susceptible to attack by water. A prominent example is poly-3-hydroxybutyrate, the renewably derived polylactic acid.
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The eluent (mobile phase) should be a good solvent for the polymer, should permit high detector response from the polymer and should wet the packing surface. The most common eluents in for polymers that dissolve at room temperature GPC are tetrahydrofuran (THF), o-dichlorobenzene and trichlorobenzene at 130–150 °C for crystalline polyalkynes and m-cresol and o-chlorophenol at 90 °C for crystalline condensation polymers such as polyamides and polyesters.
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The presence of the vinyl group allows styrene to polymerize. Commercially significant products include polystyrene, ABS, styrene-butadiene (SBR) rubber, styrene-butadiene latex, SIS (styrene- isoprene-styrene), S-EB-S (styrene-ethylene/butylene-styrene), styrene- divinylbenzene (S-DVB), styrene-acrylonitrile resin (SAN), and unsaturated polyesters used in resins and thermosetting compounds. These materials are used in rubber, plastic, insulation, fiberglass, pipes, automobile and boat parts, food containers, and carpet backing.
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Hazira Manufacturing Division (HMD) is the manufactory of Reliance Industries Limited (RIL) located at Hazira, Gujarat, India in Surat. It was commissioned in 1991–92. It is a multi-product, fully integrated complex, manufacturing a wide range of petrochemicals, polymers, polyesters and polyester intermediates. Naphtha is the main raw material of this manufactory, A Naphtha cracker facility crackes the Naphtha and feeds the downstream fiber intermediates, plastics and polyester plants.
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The weight fraction of reinforcement in this process is typically 20 to 40% of the total weight of the part. The most common resin system used for the spray-up process is general purpose or DCDP polyester; isophthalic polyesters and vinyl ester resins are also sometimes used. Fast-reacting resins with a pot life of 30 to 40 minutes are typical. The resin often contains a significant amount of filler.
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John Rex Whinfield CBE (16 February 1901 in Sutton, Surrey, England – 6 July 1966 in Dorking, Surrey) was a British chemist. Together with James Tennant Dickson, Whinfield investigated polyesters and produced and patented the first polyester fibre in 1941, which they named Terylene (also known as Dacron) equal to or surpassing nylon in toughness and resilience. He was born in Accrington, but moved out of town before the age of 4.
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Soy flour or defatted soy flour (50% protein) glue which originally replaced the more expensive casein glue for Douglas fir plywood is re-emerging as the glue of choice to replace toxic urea formaldehyde and phenol formaldehyde resin glues with a formaldehyde-free soy glue. Soy protein is used for emulsification and texturizing. Specific applications include adhesives, asphalts, resins, cleaning materials, cosmetics, inks, pleather, paints, paper coatings, pesticides/fungicides, plastics, polyesters, and textile fibres.
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Diols react as alcohols, by esterification and ether formation. Diols such as ethylene glycol are used as co-monomers in polymerization reactions forming polymers including some polyesters and polyurethanes. A different monomer with two identical functional groups, such as a dioyl dichloride or dioic acid is required to continue the process of polymerization through repeated esterification processes. A diol can be converted to cyclic ether by using an acid catalyst, this is diol cyclization.
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PTT's value as a commercial polymer has improved due to more economical and efficient methods to produce 1,3-propanediol in the 1980s by Degussa, via acrolein, and Shell via the hydroformylation of ethylene oxide. DuPont has successfully commercialized the production of this polymer via 1,3-propanediol obtained by fermentation. These developments may allow PTT to effectively compete against PBT and PET, two polyesters that have been far more successful than PTT to date.
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In order to have these types of qualities, positive resist utilize polymers with labile linkers in their back bone that can be cleaved upon irradiation or using a photo- generated acid to hydrolyze bonds in the polymer. A polymer that decomposes upon irradiation to a liquid, or more soluble product is referred to as a positive tone resist. Common functional groups that can be hydrolyzed by photo-generated acid catalyst include polycarbonates and polyesters.
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Another example is Brazilian pulp and paper manufacturer Suzano, which since 2012 produces paperboard made from Post consumer resin (PCR) by extracting fibers from long life packagingLong life packaging is packaging consisting of multiple layers that make the packaging more durable. A typical example of long life packaging is a milk carton. such as milk cartons. In 2012, more than one third of recycled PET was used as polyesters for the textile industry.
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UV-328 is a light stabilizer for a variety of plastics and other organic substrates. Its use is recommended for the stabilization of styrene homopolymers and copolymers, acrylic polymers, unsaturated polyesters, polyvinyl chloride, polyolefins, polyurethanes, polyacetals, polyvinyl butyral, elastomers and adhesives. It protects polymers and organic pigments from UV radiation and helps maintain the original appearance and physical integrity of moldings, films, sheets and fibers during outdoor weathering. The application concentration is 0.1-1 %.
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Many different materials (natural and synthetic, biodegradable and permanent) have been investigated. Most of these materials have been known in the medical field before the advent of tissue engineering as a research topic, being already employed as bioresorbable sutures. Examples of these materials are collagen and some polyesters. New biomaterials have been engineered to have ideal properties and functional customization: injectability, synthetic manufacture, biocompatibility, non-immunogenicity, transparency, nano-scale fibers, low concentration, resorption rates, etc.
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Later another use of the compound was found, namely as a flame retardant for polyesters in 1957. In addition, HCCPD was used to make a dimer. This dimer was also known as “Mirex” or “Box dimer” and was offered commercially as a flame retardant to be used in polymers such as polypropylene. In the 1970s, it was shown that the Mirex dimer degrades in the environment into kepone, a well established carcinogen.
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Like other polyesters such as PET, two main routes exist for the synthesis of PBS: the trans-esterification process (from succinate diesters) and the direct esterification process starting from the diacid. The direct esterification of succinic acid with 1,4-butanediol is the most common way to produce PBS. It consists of a two step process. First, an excess of the diol is esterified with the diacid to form PBS oligomers with elimination of water.
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In general, most aliphatic polyesters have poor mechanical properties and PEA is no exception. Little research has been done on the mechanical properties of pure PEA but one study found PEA to have a tensile modulus of 312.8 MPa, a tensile strength of 13.2 MPa, and an elongation at break of 362.1%. Alternate values that have been found are a tensile strength of ~10 MPa and a tensile modulus of ~240 MPa.
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Glycerides, which are fatty acid esters of glycerol, are important esters in biology, being one of the main classes of lipids, and making up the bulk of animal fats and vegetable oils. Esters with low molecular weight are commonly used as fragrances and found in essential oils and pheromones. Phosphoesters form the backbone of DNA molecules. Nitrate esters, such as nitroglycerin, are known for their explosive properties, while polyesters are important plastics, with monomers linked by ester moieties.
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Close-up view of microfiber cloth Microfiber cloth suitable for cleaning sensitive surfaces Microfiber (or microfibre) is synthetic fiber finer than one denier or decitex/thread, having a diameter of less than ten micrometres. A strand of silk is about one denier and about a fifth of the diameter of a human hair. The most common types of microfiber are made variously of polyesters; polyamides (e.g., nylon, Kevlar, Nomex, trogamide); and combinations of polyester, polyamide, and polypropylene.
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They subsequently studied the crystalline structures of isotactic polypropylene, isotactic polystyrene, polyesters, various polypeptides (see Peptide), and other crystallisable polymers. In 1965, Keith and his collaborators explained the mechanical strength of polymers by discovering their intercrystalline links. A team led by Keith led, including Padden, Lotz and Giannoni, produced the first chain-folded single DNA crystals in 1969. For this and their later work, the American Physical Society awarded its Polymer Physics Prize to Keith & Padden in 1973.
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The industry faces challenges from increases in cotton production elsewhere where US cotton exports had gone and shifts to less expensive synthetic fibers, such as polyesters. From 2012-2016, Missouri was ranked eighth in cotton production in the United States with the average production value of $191,004,400. Missouri soil allows for the growth of upland cotton with the average bale weighing approximately five hundred pounds. The cottonseed from Missouri cotton production is used as livestock feed.
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Glycerides, which are fatty acid esters of glycerol, are important esters in biology, being one of the main classes of lipids, and making up the bulk of animal fats and vegetable oils. Esters with low molecular weight are commonly used as fragrances and found in essential oils and pheromones. Phosphoesters form the backbone of DNA molecules. Nitrate esters, such as nitroglycerin, are known for their explosive properties, while polyesters are important plastics, with monomers linked by ester moieties.
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Polymeric crystals of PHB observed by polarizing optical microscope. Polyhydroxybutyrate (PHB) is a polyhydroxyalkanoate (PHA), a polymer belonging to the polyesters class that are of interest as bio-derived and biodegradable plastics. The poly-3-hydroxybutyrate (P3HB) form of PHB is probably the most common type of polyhydroxyalkanoate, but other polymers of this class are produced by a variety of organisms: these include poly-4-hydroxybutyrate (P4HB), polyhydroxyvalerate (PHV), polyhydroxyhexanoate (PHH), polyhydroxyoctanoate (PHO) and their copolymers.
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On 1 April 2005, the six polyester companies namely Appollo Fibres Limited (AFL), Central India Polyesters Limited (CIPL), India Polyfibres Limited (IPL), Orissa Polyfibres Limited (OPL), Recron Synthetics Limited (RSL) and Silvassa Industries Private Limited (SIPL) have been amalgamated with IPCL. This marks the entry of the Company in the polyester sector. The polyester units are based in Hoshiarpur (Punjab), Nagpur (Maharashtra), Barabanki (Uttar Pradesh), Baulpur (Orissa), Allahabad (Uttar Pradesh) and Silvassa (Dadra and Nagar Haveli).
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Sculptures utilize polyesters applied directly onto the human body or mold. Hyperrealism requires a high level of technical prowess and virtuosity to simulate a false reality. As such, Hyperrealism incorporates and often capitalizes upon photographic limitations such as depth of field, perspective and range of focus. Anomalies found in digital images, such as fractalization, are also exploited to emphasize their digital origins by some Hyperrealist painters, such as Chuck Close, Denis Peterson, Bert Monroy and Robert Bechtle.
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Figure 3. Incorporation of Bithionol into the Polymer Backbone This method involves using chemical reactions to incorporate antimicrobial agents into the polymeric backbones. Polymers with biologically active groups, such as polyamides, polyesters, and polyurethanes are desirable as they may be hydrolyzed to active drugs and small innocuous molecules. For example, a series of polyketones have been synthesized and studied, which show an inhibitory effect on the growth of B. subtilis and P. fluorescens as well as fungi, A. niger and T. viride.
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Many plastics are completely amorphous, such as: all thermosets; polystyrene and its copolymers; and polymethyl methacrylate. However, some plastics are partially crystalline and partially amorphous in molecular structure, giving them both a melting point, the temperature at which the attractive intermolecular forces are overcome, and also one or more glass transitions, the temperatures above which the extent of localized molecular flexibility is substantially increased. These so-called semi-crystalline plastics include: polyethylene, polypropylene, polyvinyl chloride, polyamides (nylons), polyesters and some polyurethanes.
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Danimer Scientific's PHA has received several certifications for biodegradability including: anaerobic and aerobic digestion in soil, freshwater, marine, industrial and home composting. The patented version of Danimer Scientific's mcl-PHA is known as Nodax™, and it is the primary product developed for commercial manufacturing. Danimer Scientific's Nodax™ PHA is a class of bioplastics produced from bacterial microorganisms that store PHA polyesters for energy in their cell walls. These microbes feed upon plant-based oils procured from non-food sources.
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Acrylated epoxies are useful as coatings on metallic substrates, and result in glossy hard coatings. Acrylated urethane oligomers are typically abrasion resistant, tough, and flexible making ideal coatings for floors, paper, printing plates, and packaging materials. Acrylated polyethers and polyesters result in very hard solvent resistant films, however, polyethers are prone to UV degradation and therefore are rarely used in UV curable material. Often formulations are composed of several types of oligomers to achieve the desirable properties for a material.
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A number bioplastic classes have been synthesized from plant and animal derived fats and oils. Polyurethanes, polyesters, epoxy resins and a number of other types of polymers have been developed with comparable properties to crude oil based materials. The recent development of olefin metathesis has opened a wide variety of feedstocks to economical conversion into biomonomers and polymers. With the growing production of traditional vegetable oils as well as low cost microalgae derived oils, there is huge potential for growth in this area.
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At the beginning of this chapter, it was mentioned that FDCA is a chemically stable compound. This property has been well benefited in industry – FDCA as most of polycarboxylic acids can be an ingredient of fire foams. Such foams help to extinguish fires in a short time caused by polar and non-polar solvents. FDCA has a large potential as a replacement for terephthalic acid, a widely used component in various polyesters, such as polyethylene terephthalate (PET) and polybutyleneterephthalate (PBT).
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Step-growth polymers like polyesters, polyamides and polycarbonates can be degraded by solvolysis and mainly hydrolysis to give lower molecular weight molecules. The hydrolysis takes place in the presence of water containing an acid or a base as catalyst. Polyamide is sensitive to degradation by acids and polyamide mouldings will crack when attacked by strong acids. For example, the fracture surface of a fuel connector showed the progressive growth of the crack from acid attack (Ch) to the final cusp (C) of polymer.
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Condensation polymerization is an important class of step-growth polymerization, which is formed simply by the reaction of two monomers and results in the release of a water molecule. Since these polymers are typically made up of two or more monomers, the resulting end groups are from the monomer functionality. Examples of condensation polymers can be seen with polyamides, polyacetals and polyesters. An example of polyester is polyethylene terephthalate (PET), which is made from the monomers terephthalic acid and ethylene glycol.
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About 50 billion single-use plastic water bottles made of polyethylene terephthalate (PET) are produced in the United States each year, and most are discarded. According to the National Association for PET Container Resources, the recycling rate for PET has held steady at 31% since 2013. Polyesters like PET can be broken down through hydrolytic degradation: the ester linkage is cut by a water molecule. The reaction proceeds differently in acidic or alkaline conditions, but works best at temperatures between 200 - 300 °C.
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Historically, the main use was as a raw material in the production of pigments for lead paints, but such paints have been superseded by less toxic paints based on titanium dioxide. Other industrial uses included heat stabilization in nylon and polyesters, and in coatings of photothermographic paper. Since around the year 2000, lead(II) nitrate has begun to be used in gold cyanidation. Lead(II) nitrate is toxic and must be handled with care to prevent inhalation, ingestion and skin contact.
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An important use of adipoyl chloride is polymerization with an organic di-amino compound to form a polyamide called nylon or polymerization with certain other organic compounds to form polyesters. Phosgene (carbonyl dichloride, Cl–CO–Cl) is a very toxic gas that is the dichloride of carbonic acid (HO–CO–OH). Both chloride radicals in phosgene can undergo reactions analogous to the preceding reactions of acyl halides. Phosgene is used a reactant in the production of polycarbonate polymers, among other industrial applications.
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Thermosetting plastics are divided into two types: formaldehyde cross-linking type and other cross-linking type. Thermosets includes phenolic resins, polyesters and epoxy resins, all of which are used widely in composite materials when reinforced with stiff fibers such as fiberglass and aramids. Since crosslinking stabilises the thermoset polymer matrix of these materials, they have physical properties more similar to traditional engineering materials like steel. However, their very much lower densities compared with metals makes them ideal for lightweight structures.
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Plastics which have been around, and which are in current widespread use, include polyethylene, polypropylene, polyvinyl chloride (PVC), polystyrene, nylons, polyesters, acrylics, polyurethanes, and polycarbonates and also rubbers which have been around are natural rubber, styrene-butadiene rubber, chloroprene, and butadiene rubber. Plastics are generally classified as commodity, specialty and engineering plastics. Polyvinyl chloride (PVC) is widely used, inexpensive, and annual production quantities are large. It lends itself to a vast array of applications, from artificial leather to electrical insulation and cabling, packaging, and containers.
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In interfacial polycondensation, the two reactants in a polycondensation meet at an interface and react rapidly. The basis of this method is the classical Schotten-Baumann reaction between an acid chloride and a compound containing an active hydrogen atom, such as an amine or alcohol, polyesters, polyurea, polyurethane. Under the right conditions, thin flexible walls form rapidly at the interface. A solution of the pesticide and a diacid chloride are emulsified in water and an aqueous solution containing an amine and a polyfunctional isocyanate is added.
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Polymers are the raw materials (the resins) used to make what are commonly called plastics. Plastics are the final product, created after one or more polymers or additives have been added to a resin during processing, which is then shaped into a final form. Polymers that have been around, and that are in current widespread use, include carbon-based polyethylene, polypropylene, polyvinyl chloride, polystyrene, nylons, polyesters, acrylics, polyurethane, and polycarbonates, and silicon-based silicones. Plastics are generally classified as "commodity", "specialty" and "engineering" plastics.
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Animal fibers include silk, but generally are long hairs of animals such as sheep (wool), goat (angora, or cashmere goat), rabbit (angora), llama, alpaca, dog, cat, camel, yak, and muskox (qiviut). Plants used for fibers include cotton, flax (for linen), bamboo, ramie, hemp, jute, nettle, raffia, yucca, coconut husk, banana fiber, soy and corn. Rayon and acetate fibers are also produced from cellulose mainly derived from trees. Common synthetic fibers include acrylics, polyesters such as dacron and ingeo, nylon and other polyamides, and olefins such as polypropylene.
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Two molecules of lactic acid can be dehydrated to lactide, a cyclic lactone. A variety of catalysts can polymerise lactide to either heterotactic or syndiotactic polylactide, which as biodegradable polyesters with valuable (inter alia) medical properties are currently attracting much attention. Nowadays, lactic acid is used as a monomer for producing polylactic acid (PLA) which later has application as biodegradable plastic. This kind of plastic is a good option for substituting conventional plastic produced from petroleum oil because of low emission of carbon dioxide.
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Een bijzonder energiek ondernemer - Rento Wolter Hendrik Hofstede Crull (1863-1938): pioneer van de elektriciteits voorziening in Nederland Zutphen, Netherlands: Historisch Centrum Overijsssel & Walberg Pers, 2009. pp: 137- 138 In 1969 Algemene Kunstzijde Unie and Koninklijke Zout Organon merged, forming Akzo. In the following years the company made a number of critical acquisitions; Armour and Company in 1970,AkzoNobel company history , fundinguniverse.com Levis Paints in 1985, specialty chemicals division of Stauffer in 1987 and divested its polyamides and polyesters plastics engineering business to DSM in 1992.
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Isosorbide is a bicyclic chemical compound from the group of diols and the oxygen-containing heterocycles, containing two fused furan rings. The starting material for isosorbide is D-sorbitol, which is obtained by catalytic hydrogenation of D-glucose, which is in turn produced by hydrolysis of starch. Isosorbide is discussed as a plant-based platform chemical from which biodegradable derivatives of various functionality can be obtained. Isosorbide is currently of great scientific and technical interest as a monomer building block for biopolymeric polycarbonates, polyesters, polyurethanes and epoxides.
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A unique class of partially crystalline aromatic polyesters based on p-hydroxybenzoic acid and related monomers, liquid-crystal polymers are capable of forming regions of highly ordered structure while in the liquid phase. However, the degree of order is somewhat less than that of a regular solid crystal. Typically, LCPs have a high mechanical strength at high temperatures, extreme chemical resistance, inherent flame retardancy, and good weatherability. Liquid-crystal polymers come in a variety of forms from sinterable high temperature to injection moldable compounds.
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The typical example are polyesters, polyamides and polyethers. It is sometimes confused by condensation previous definition of condensation polymerization. Polyaddition is a type of step-growth polymerization of which chain growth is based on addition reaction between two molecules of various degree of polymerization. The typical example for polyaddition is the synthesis of polyurethane. Compared to chain-growth polymerization, where the production of the growing chaingrowth is based on the reaction between polymer with active center and monomer, step-growth polymerization doesn’t have initiator or termination.
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A generic representation of a step-growth polymerization. (Single white dots represent monomers and black chains represent oligomers and polymers) Comparison of molecular weight vs conversion plot between step-growth and living chain-growth polymerization Step-growth polymerization refers to a type of polymerization mechanism in which bi-functional or multifunctional monomers react to form first dimers, then trimers, longer oligomers and eventually long chain polymers. Many naturally occurring and some synthetic polymers are produced by step-growth polymerization, e.g. polyesters, polyamides, polyurethanes, etc.
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The antenna can take different shapes: a spiral, a single dipole antenna, two dipoles with one dipole perpendicular to another, or a folded dipole. The antenna length and geometry depends on the frequency at which the tag operates. Chip and antenna are embedded onto a thin plastic substrate of 100 to 200 nm, for example polymer, PVC, Polyethylenetherephtalate (PET), phenolics, polyesters, styrene, or paper via copper etching or hot stamping. Fastest and cheapest process is via screen printing using conductive ink containing copper, nickel, or carbon.
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In industry, the improvement of the PBS synthesis allowed the large scale production of this polymer. The Japanese company Showa High Polymer, built in 1993 a semi-commercial plant able to produce 3,000 tons of polymer per year. Sold under the tradename Bionolle, these polyesters are synthesized via melt condensation polymerization followed by a chain-extension with a diisocyanate. Much later, in April 2003, Mitsubishi Chemicals built a 3,000 tons/year capacity and launched to the market a PBS named GS Pla (Green and Sustainable Plastic).
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Specific highly brominated molecules can also be added that participate in the polymerisation process For example, tetrabromobisphenol A can be added to polyesters or epoxy resins, where it becomes part of the polymer. Epoxies used in printed circuit boards are normally made from such flame retardant resins, indicated by the FR in the abbreviation of the products (FR-4 and FR-2). In some cases the bromine containing compound may be added after polymerisation. For example, decabromodiphenyl ether can be added to the final polymers.
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SP Chemicals engages in the manufacture and sale of the chemical industry's basic building blocks - caustic soda, chlorine, hydrogen and its related downstream products. Their products are materials widely used in various applications across a diverse range of industries. Products include: aniline, caustic soda, chlorine, chlorobenzene, nitrochlorobenzene, nitrobenzene, vinyl chloride monomer (VCM). To further drive its growth, SP Chemicals plans to invest approximately RMB1.1 billion in facilities for the production of styrene monomer, an intermediate raw chemical used in making polystyrene plastics, protective coatings, polyesters and resins.
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Higher end billiard balls are made from phenolic resins, as opposed to the polyesters used in less expensive sets. Sometimes people select fibre reinforced phenolic resin parts because their coefficient of thermal expansion closely matches that of the aluminium used for other parts of a system, as in early computer systems J. G. Ferguson, W. E. Grutzner, D. C. Koehler, R. S. Skinner, M. T. Skubiak, and D. H. Wetherell. "No. 1 ESS Apparatus and Equipment". The Bell System Technical Journal. 1964\. p. 2417.
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For the Open Conference, Tefilin brought back Ira Terrell, this time teaming up with former Royal Tru-Orange import Larry Pounds. Tefilin was tied with the CDCP Road Builders with ten wins and eight losses after 18 games in the eliminations. Both sophomore ballclubs missed out a semifinal berth and were two games behind the fourth qualifier Toyota Super Diesels. The Polyesters signed up Norman Black, who played for the Detroit Pistons in the Southern California Summer Pro league, as their import in the Reinforced Filipino Conference.
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As a reactive monomer, ethyl acrylate is used in homopolymers and copolymers with e.g. ethene, acrylic acid and its salts, amides and esters, methacrylates, acrylonitrile, maleic esters, vinyl acetate, vinyl chloride, vinylidene chloride, styrene, butadiene and unsaturated polyesters. Copolymers of acrylic acid ethyl ester with ethene (EPA/ethylene-ethyl acrylate copolymers) are suitable as adhesives and polymer additives, just like ethene vinyl acetate copolymers. Copolymers with acrylic acid increase the cleaning effect of liquid detergents, copolymers with methacrylic acid are used as gastric juices tablet covers (Eudragit).
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PETases are an esterase class of enzymes that catalyze the hydrolysis of polyethylene terephthalate (PET) plastic to monomeric mono-2-hydroxyethyl terephthalate (MHET). The idealized chemical reaction is (where n is the number of monomers in the polymer chain): :(ethylene terephthalate)n \+ H2O → (ethylene terephthalate)n-1 \+ MHET Trace amount of the PET breaks down to bis(2-hydroxyethyl) terephthalate (BHET). PETases can also break down PEF- plastic (polyethylene-2,5-furandicarboxylate), which is a bioderived PET replacement. PETases can't catalyze the hydrolysis of aliphatic polyesters like polybutylene succinate or polylactic acid.
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A variety of hydroxylic compounds can add as nucleophiles, forming either enol or ester products. As examples, a water molecule easily adds to ketene to give 1,1-dihydroxyethene and acetic anhydride is produced by the reaction of acetic acid with ketene. Reactions between diols (HO−R−OH) and bis-ketenes (O=C=CH−R′−CH=C=O) yield polyesters with a repeat unit of (−O−R−O−CO−R′−CO). Ethyl acetoacetate, an important starting material in organic synthesis, can be prepared using a diketene in reaction with ethanol.
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Invista makes extensive use of co-branding in their marketing of Coolmax and other clothing materials, partnering with their customers to increase awareness of their product among end consumers. Like other polyester fabrics, Coolmax is flammable and has a relatively low melting point (~255 °C), giving clothes made from it a tendency to melt and fuse to the wearer's skin when exposed to high heat. This has led to Coolmax and other polyesters (along with acrylic and rayon) being restricted or banned in certain high-fire-risk applications, such as firefighting and front-line combat.
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Researchers Tony Jia and Kuhan Chandru have proposed that membraneless polyesters droplets could have been significant in the Origins of Life. Given the "messy" nature of prebiotic chemistry, the spontaneous generation of these combinatorial droplets may have played a role in early cellularization before the innovation of lipid vesicles. Protein function within and RNA function in the presence of certain polyester droplets was shown to be preserved within the droplets. Additionally, the droplets have scaffolding ability, by allowing lipids to assemble around them that may have prevented leakage of genetic materials.
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Plants used for fibers include cotton, flax (for linen), bamboo, ramie, hemp, jute, nettle, raffia, yucca, coconut husk, banana trees, soy and corn. Rayon and acetate fibers are also produced from cellulose mainly derived from trees. Common synthetic fibers include acrylics, polyesters such as dacron and ingeo, nylon and other polyamides, and olefins such as polypropylene. Of these types, wool is generally favored for crochet, chiefly owing to its superior elasticity, warmth and (sometimes) felting; however, wool is generally less convenient to clean and some people are allergic to it.
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Nylons are condensation polymers or copolymers, formed by reacting difunctional monomers containing equal parts of amine and carboxylic acid, so that amides are formed at both ends of each monomer in a process analogous to polypeptide biopolymers. Most nylons are made from the reaction of a dicarboxylic acid with a diamine (e.g. PA66) or a lactam or amino acid with itself (e.g. PA6). In the first case, the "repeating unit" consists of one of each monomer, so that they alternate in the chain, similar to the so-called ABAB structure of polyesters and polyurethanes.
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For example, some fully aromatic nylons (known as "aramids") are polymerized with the addition of diacids like terephthalic acid (→ Kevlar, Twaron) or isophthalic acid (→ Nomex), more commonly associated with polyesters. There are copolymers of PA 66/6; copolymers of PA 66/6/12; and others. In general linear polymers are the most useful, but it is possible to introduce branches in nylon by the condensation of dicarboxylic acids with polyamines having three or more amino groups. The general reaction is: 600px Two molecules of water are given off and the nylon is formed.
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The diacid chloride monomers were placed in an organic solvent (benzene) and the diamene monomers in a water phase, such that when the monomers reached the interface they would polymerize. Since 1959, interfacial polymerization has been extensively researched and used to prepare not only polyamides but also polyanilines, polyimides, polyurethanes, polyureas, polypyrroles, polyesters, polysulfonamides, polyphenyl esters and polycarbonates. In recent years, polymers synthesized by interfacial polymerization have been used in applications where a particular topological or physical property is desired, such as conducting polymers for electronics, water purification membranes, and cargo-loading microcapsules.
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A. V. Lourenço W. H. Carothers The synthesis of succinic acid based polyesters was first performed in 1863. In that time the Portuguese professor Agostinho Vicente Lourenço described in his "Recherche sur les composés polyatomiques" (Research on polyatomic compounds), the reaction between succinic acid and ethylene glycol to form what he named "succino-ethylenic acid". He noticed that this acid was losing water when it was heated at high temperatures (300 °C) and that a crystalline mass when obtained after cooling. Unfortunately, Lourenço did not study much the structure of the material he obtained.
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As a result of increasing biodiesel production, formation of the byproduct, crude glycerol, has also increased. While glycerol is commonly used in food, pharmaceuticals, cosmetics, and other industries, increased production of crude glycerol has become very expensive to purify and utilize in these industries. Because of this, researchers are interested in finding new economical ways to utilize low-grade glycerol products. Biotechnology is one such technique: using particular enzymes to break down crude glycerol to form products such as 1,3-propanediol, 1,2-propanediol, succinic acid, dihydroxyacetone (glycerone), hydrogen, polyglycerols, and polyesters.
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For some polymers, it is possible to convert them back into monomers, for example, PET can be treated with an alcohol and a catalyst to form a dialkyl terephthalate. The terephthalate diester can be used with ethylene glycol to form a new polyester polymer, thus making it possible to use the pure polymer again. An estimated 60 companies are pursuing chemical recycling as of 2019. In 2019, Eastman Chemical Company announced initiatives for methanolysis of polyesters and polymer gasification to syngas designed to handle a greater variety of used material.
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Hexafluoro-propan-2-ol is prepared from hexafluoropropylene through hexafluoroacetone, which is then hydrogenated.Günter Siegemund, Werner Schwertfeger, Andrew Feiring, Bruce Smart, Fred Behr, Herward Vogel, Blaine McKusick “Fluorine Compounds, Organic” in Ullmann's Encyclopedia of Industrial Chemistry, John Wiley & Sons, 2007. :(CF3)2CO + H2 → (CF3)2CHOH Hexafluoro- propan-2-ol is a speciality solvent for some polar polymers and organic synthesis. It is especially effective for solubilizing a wide range of polymers, including those that are not soluble in the most common organic solvents, such as: polyamides, polyacrylonitriles, polyacetals, polyesters (e.g.
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A thermosetting resin is used as a main component, and a plastic which forms a product is formed by a cross- linking curing process in combination with various necessary additives. It is liquid in the early stage of the manufacturing or molding process, and it is insoluble and infusible after curing, and it cannot be melted or softened again. Common thermosetting plastics are phenolic plastics, epoxy plastics, aminoplasts, unsaturated polyesters, alkyd plastics, and the like. Thermoset plastics and thermoplastics together constitute the two major components of synthetic plastics.
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Crambe oil is an inedible seed oil, extracted from the seeds of the Crambe abyssinica, a multibranched annual plant that is native to the Ethiopian Highlands also known as Abyssinia. The oil has been shown to consist of 55-60% erucic acid. The Australian Farm Diversification Information Service writes: :Intermediate product derived from high erucic acid oil include: triglycerides; erucamides; amines, behenic acid; erucyl alcohol; behenyl alcohol; wax esters; fatty acids; brassylic acid and pelargonic acid. These products are used to manufacture a multitude of industrial consumer items such as lubricants; heat transfer fluids; surfactants and coatings; cosmetics; polyesters; plastics and nylons.
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In 2018, The Mayor Gallery displayed Mallary's computer-generated sculpture, Quad 3 , along with his computer drawings in the exhibition, "Writing New Codes: 3 Pioneers in Computer Art 1969-1977." The Mayor Gallery sold Quad 3 to the Tate Gallery in 2019. Mallary had liver problems in later life, probably due to the toxicity of the liquid polyesters he had used to create his abstract expressionist sculptures in the 1950s and '60s. He lived in Conway, Massachusetts, and died of complications due to leukemia at Cooley Dickinson Hospital in Northampton, Massachusetts in 1997, at age 79.
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Isosorbide has a high thermal stability and is by now well available from renewable raw materials. This makes isosorbide of interest as a monomer for thermoplastic (bio)polymers such as polyesters and polycarbonates, as well as for thermosets such as polyurethanes or epoxy resins. The hydroxy groups can be converted into the primary amino groups via the tosylates and azides or by addition of acrylonitrile followed by hydrogenation into the corresponding aminopropyl derivatives.US-Patentanmeldung US 2010/0130759A1 Novel functional compounds with an isosorbide or isosorbide isomer core, production process and uses of these compounds, invent1: J.-P.
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However, the inherently lower reactivity of the secondary hydroxyl groups in isosorbide cause in comparison lower molecular weights and high residual contents of terephthalic acid, which leads to the insufficient chemical stability of the resulting polymers. Therefore, today's polyesters with isosorbide and monoethylene glycol are examined as diol components that show improved properties such as less discoloration.US-Patentanmeldung US 2006/0173154A1 Process for making low color poly(ethylene-co-isosorbide) terephthalate polymer, invent1: L. Charbonneau, assign1: E.I. du Pont de Nemours and Company, veröffentlicht am 3. August 2006 Isosorbide is of particular interest as a monomer for polycarbonates,M.
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1,2,4-Butanetriol is a clear or slightly yellow, odorless, hygroscopic, flammable, viscous liquid. It is an alcohol with three hydrophilic alcoholic hydroxyl groups. It is similar to glycerol and erythritol. It is chiral, with two possible enantiomers. 1,2,4-Butanetriol is used in the manufacture of butanetriol trinitrate (BTTN), an important military propellant. 1,2,4-Butanetriol is also used as a precursor for two cholesterol-lowering drugs, Crestor and Zetia, which are derived from D-3,4-dihydroxybutanoic acid, by using 3-hydroxy-gamma-butyrolactone as a chiral synthon It is used as one of the monomers for manufacture of some polyesters and as a solvent.
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Lead nitrate has been used as a heat stabiliser in nylon and polyesters, as a coating for photothermographic paper, and in rodenticides. Heating lead nitrate is convenient means of making nitrogen dioxide :2 Pb(NO3)2 → 2 PbO + 4 NO2 \+ O2 In the gold cyanidation process, addition of lead(II) nitrate solution improves the leaching process. Only limited amounts (10 to 100 milligrams lead nitrate per kilogram gold) are required. In organic chemistry, it may be used in the preparation of isothiocyanates from dithiocarbamates.. Its use as a bromide scavenger during SN1 substitution has been reported.
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The intermolecular forces in polymers can be affected by dipoles in the monomer units. Polymers containing amide or carbonyl groups can form hydrogen bonds between adjacent chains; the partially positively charged hydrogen atoms in N-H groups of one chain are strongly attracted to the partially negatively charged oxygen atoms in C=O groups on another. These strong hydrogen bonds, for example, result in the high tensile strength and melting point of polymers containing urethane or urea linkages. Polyesters have dipole-dipole bonding between the oxygen atoms in C=O groups and the hydrogen atoms in H-C groups.
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Dipole bonding is not as strong as hydrogen bonding, so a polyester's melting point and strength are lower than Kevlar's (Twaron), but polyesters have greater flexibility. Polymers with non-polar units such as polyethylene interact only through weak Van der Waals forces. As a result, they typically have lower melting temperatures than other polymers. When a polymer is dispersed or dissolved in a liquid, such as in commercial products like paints and glues, the chemical properties and molecular interactions influence how the solution flows and can even lead to self-assembly of the polymer into complex structures.
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Polyesters and polyamides are examples of condensation polymers formed by step-growth polymerization. Carothers worked out the theory of step-growth polymerization and derived the Carothers equation which relates the average degree of polymerization to the fractional conversion (or yield) of monomer into polymer. This equation shows that for a high molecular weight, a very high fractional conversion is needed (for step-growth polymers only). Hill also produced a synthetic fiber that was elastic and strong by combining glycols and diacids and heating under reduced pressure, using a molecular still to remove the last traces of water produced in the condensation reaction.
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The concept of liquid roofing has existed since (at least) the early 1800s, when natural bitumen was combined with jute, straw, rag felt and other man made materials to provide a waterproofing solution for roofs. In the early twentieth century the manufacture of liquid roof coatings became a commercial activity, with the earliest coatings being based on liquefied rubber. The 1960s and 1970s saw the introduction of acrylics, acrylic emulsions, styrene butadienes and unsaturated polyesters, which led to improved quality and durability of the coatings. In 1975, the first water based elastomeric roof coatings were introduced.
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In 2019, Eastman began commercial-scale chemical recycling for a broad set of waste plastics that would otherwise be placed in a landfill or incinerated. Eastman Advanced Circular Recycling technologies complement mechanical recycling by processing a wide spectrum of waste plastics that traditional recycling methods cannot, including polyesters, polypropylene, polyethylene, and polystyrene. These waste plastics are derived from a variety of sources, including single-use plastics, textiles, and cuttings from discarded carpet. Eastman's recycling technologies - carbon renewal technology and polyester renewal technology - provide a true circular solution of infinite recycling for materials, allowing them to be reused repeatedly.
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Corynebacterium glutamicum is one of the most important bacterial species with an annual production of more than two million tons of amino acids, mainly L-glutamate and L-lysine. Since some bacteria have the ability to synthesize antibiotics, they are used for medicinal purposes, such as Streptomyces to make aminoglycoside antibiotics. Fermenting tanks with yeast being used to brew beer A variety of biopolymers, such as polysaccharides, polyesters, and polyamides, are produced by microorganisms. Microorganisms are used for the biotechnological production of biopolymers with tailored properties suitable for high-value medical application such as tissue engineering and drug delivery.
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Dimethylaminoethyl acrylate is a acrylic acid ester carrying a functional group with basic properties. It therefore reacts as an α, β-unsaturated carbonyl compound in an addition reaction with nucleophiles in a Michael addition. As a reactive monomer, 2-dimethylaminoethyl acrylate forms homopolymers and copolymers with acrylic acid and acrylic acid salts, amides and esters, as well as methacrylates, acrylonitrile, maleic acid esters, vinyl acetate, chloroethene (vinyl chloride), 1,1-dichloroethene, styrene, 1,3-butadiene, unsaturated polyesters and drying oils. In copolymers, DMAEA improves their nucleophilicity, basicity, water solubility and adhesion to polar negatively charged substrates, as well as dyeability of acrylic fibers with anionic dyes.
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This is the second polymer used with the step 1 product to create the copolymer PBAT. TBOT is used to catalyze the transesterification of the polyesters of adipic acid and DMT to generate the random, copolymer PBAT. This is a random copolymer, because there is no control on the dispersity of the polymer chain lengths or block structuring in the copolymerization reactions; repeat positions are not controlled. If A = polyester of adipic acid and B = polyester of DMT, each with 1,4-butanediol, then the chain structuring could look like any of these: AABABBABA or ABABAAAABB or ABABABBBBA; there is no selectivity for A and B reacting with themselves or each other.
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He inherited the problem from famed chemist Wallace Carothers who was also working at DuPont at the time. Within a week, Hanford and his two assistants had found a solution that yielded ninety-six percent of Carothers’ desired polymer. Solving this problem furthered Hanford's interest in polyamides and polyesters. He soon began to work with di-isocyanates by studying reactions that contained hydroxyl, carboxyl, amide, and amine components. On May 24, 1939, Hanford and Donald Holmes filed a patent titled “Process for Making Polymeric Products and for Modifying Polymeric Products.” This patent was the development that would eventually land Hanford in the Inventors Hall of Fame.
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Most natural polymers being employed at early stage of human society are of condensation type. The synthesis of first truly synthetic polymeric material, bakelite, was announced by Leo Baekeland in 1907, through a typical step- growth polymerization fashion of phenol and formaldehyde. The pioneer of synthetic polymer science, Wallace Carothers, developed a new means of making polyesters through step-growth polymerization in 1930s as a research group leader at DuPont. It was the first reaction designed and carried out with the specific purpose of creating high molecular weight polymer molecules, as well as the first polymerization reaction whose results had been predicted beforehand by scientific theory.
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The Somalitex factory, whose 154 automated looms work 14 hours a day, turning out nearly 14 million meters (about 15 million yards) of cloth annually the Factory employed three thousand workers. The Somalitex futas vary in thickness, colour, and design and most shops in the marketplace stock them as well as the imported polyesters. The latter, although impractical in the tropical heat, easily torn and expensive, seem to have captured the taste of Somali women by their bright patterns and varied textures. Given the ideal climate for cotton plantation in Balcad, The state-owned textile plants at Balcad could supply the local market (now not operating).
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By contrast, polyester resins are usually made available in a 'promoted' form, such that the progress of previously-mixed resins from liquid to solid is already underway, albeit very slowly. The only variable available to the user is to change the rate of this process using a catalyst, often Methyl-Ethyl-Ketone-Peroxide (MEKP), which is very toxic. The presence of the catalyst in the final product actually detracts from the desirable properties, so that small amounts of catalyst are preferable, so long as the hardening proceeds at an acceptable pace. The rate of cure of polyesters can therefore be controlled by the amount and type of catalyst as well as by the temperature.
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This field of research was brought into the institute by the arrival in 1964 of Professor Eduard Hála and his team of physical chemists to the newly built site in the Prague suburban area of Suchdol-Lysolaje. Gradually new branches of chemical engineering and chemical technology research were being developed such as reaction engineering, homogeneous catalysis, studies of Non-Newtonian fluids, sublimation, separation processes, dynamics and control of chemical systems etc. Most of these new topics were introduced as necessary support to a large and long-term project of development of a complete production technology of terephthalic acid a polyesters. In 1989 several restructurings had been carried out that lead to a gradual decrease of staff by 50%.
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As a highly functionalized, chiral compound, levoglucosenone has uses as a building block in organic synthesis to produce a wide variety of natural and non-natural compounds. Recently, the Australian company Circa developed the Furacell™ technology, a continuous process to convert a wide range of cellulosic biomass into levoglucosenone. From then on, levoglucosenone has been considered a promising bio-renewable platform for the production of commodity chemicals, being especially interesting the new insight provided by Huber and co-workers into how to transform this molecule into α,ω-diols, monomers for the production of polyesters and polyurethanes. Nowadays, the spotlight is on the use of heterogeneous catalysts to yield hydrogenation and hydrogenolysis derived products.
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Formation of hydroxymethyl-butyrolactone Dihydrolevoglucosenone can be used as a bio-based building block to produce a number of higher value chemicals such as drugs, flavours and fragrances and specialty polymers. The oxidation of dihydrolevoglucosenone with peracids such as peracetic acid in acetic acid produces optically pure 5-hydroxymethyldihydrofuranone [(S) - (+) - 4-hydroxymethyl-γ-butyrolactone], from which zalcitabine (2'-3'-dideoxycytidine, ddC), formerly a HIV drug, is available. In a two-step hydrogenation process with a metal catalyst – first at 60 °C then at 180 °C – 1,6-hexanediol is mainly obtained via several intermediates. 1,6-hexanediol can be used as a starting material for the production of polyesters, polyurethanes and diamine 1,6-diaminohexane.
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Carothers and his team synthesized a number of different polyamides including polyamide 6.6 and 4.6, as well as polyesters. General condensation polymerization reaction for nylon It took DuPont twelve years and US$27 million to refine nylon, and to synthesize and develop the industrial processes for bulk manufacture. With such a major investment, it was no surprise that Du Pont spared little expense to promote nylon after its introduction, creating a public sensation, or "nylon mania". Nylon mania came to an abrupt stop at the end of 1941 when the US entered World War II. The production capacity that had been built up to produce nylon stockings, or just nylons, for American women was taken over to manufacture vast numbers of parachutes for fliers and paratroopers.
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2,5-Furandicarboxylic acid (FDCA) is an organic chemical compound consisting of two carboxylic acid groups attached to a central furan ring. It was first reported as dehydromucic acid by Rudolph Fittig and Heinzelmann in 1876, who produced it via the action of concentrated hydrobromic acid upon mucic acid. It can be produced from certain carbohydrates and as such is a renewable resource, it was identified by the US Department of Energy as one of 12 priority chemicals for establishing the “green” chemistry industry of the future. Furan-2,5-dicarboxylic acid (FDCA) has been suggested as an important renewable building block because it can substitute for terephthalic acid (PTA) in the production of polyesters and other current polymers containing an aromatic moiety.
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Raw or unprocessed crude oil is not generally useful in industrial applications, although "light, sweet" (low viscosity, low sulfur) crude oil has been used directly as a burner fuel to produce steam for the propulsion of seagoing vessels. The lighter elements, however, form explosive vapors in the fuel tanks and are therefore hazardous, especially in warships. Instead, the hundreds of different hydrocarbon molecules in crude oil are separated in a refinery into components that can be used as fuels, lubricants, and feedstocks in petrochemical processes that manufacture such products as plastics, detergents, solvents, elastomers, and fibers such as nylon and polyesters. Petroleum fossil fuels are burned in internal combustion engines to provide power for ships, automobiles, aircraft engines, lawn mowers, dirt bikes, and other machines.
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Although there are similarities between the molecular structure of nylon 46 and that of nylon 66, the higher number of amide groups per given chain length and the more symmetrical chain structure of nylon 46 result in the higher melting temperature of 295 °C, a higher crystallinity, and a faster rate of crystallization. Nylon 46’s crystallinity is approximately 70%, compared with 50% for nylon 66. This results in a high heat distortion temperature of 190 °C for unreinforced nylon 46 and 290 °C for glass fiber reinforced nylon 46. These features give nylon 46 a technical edge over other engineering plastics like polyamide 6 and 66, polyesters and semi-aromatic polyamides (PPAs) with regard to heat resistance, mechanical properties at elevated temperatures, wear and friction behavior.
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Since polymer blends are basically unstable, they undergo stabilization during melt processing, at a nano-level combined with compatibilized material.Halahmi, I., Erez, O., Erez, A., (2011), Process for Producing Compatibilized Polymer Blends, US Patent 8,026,309 B2 The novel polymeric alloy core layer/s is made of a high performance polymer compound with a storage modulus of ≥1400 MPa at 23 °C, measured by Dynamic Mechanical Analysis (DMA) at a frequency of 1 Hz according to ASTM D4065; or an ultimate tensile strength of at least 30 MPa. The outer layers are usually made of a polyethylene or polypropylene polymer, with a blend or alloy with other polymers, fillers, additives, fibers and elastomers. The high performance alloys of polyamides, polyesters, and polyurethanes are combined with polypropylene, copolymers, block copolymers, blends and/or other combinations.
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McMurray, M. 2009. WRVS Uniform 1939-1945 The uniform was not free however, and a full suit uniform, coat, hat and scarf cost £9 4s 7d in 1940, about two weeks of the average man's wages.McMurray, M. 2009. WVS Uniform 1939-1945, page 13 The first free WVS uniform would not be introduced until 1953 when those WVS members who were part of the Civil Defence Corps were issued with a free dress, beret and overcoat. The uniform was not compulsory, except for those carrying out certain roles (such as manning a mobile canteen) and many members wore WVS overalls or just their membership badge. The WVS uniform changed very little over the years, the first change was in 1966, when the cut of the suits was altered to make them more fashionable, and then in the 1970s polyesters were introduced.
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Maoming China has been a city of local environmental dispute, surrounding the municipal government sponsored Para-Xylene (PX) Industry, which is a chemical used in manufacturing plastics, such as those in water bottles and polyesters. The industry has been promoted in Maoming for its economic benefits due to the jobs provided by the factories. Despite the industry's economic benefits, citizens began to protest in 2014 as there was increasing concern for the chemical's environmental and health risks to the citizens of the city. To counteract the environmentalist social movement, the government took action by creating an agreement that all civilians must sign stating they will not engage in protests or speak of the industry negatively, which high school students had to sign in order to graduate, as well as implementing an education campaign by providing lectures to the citizens on PX project.
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Converting companies are companies that specialize in modifying or combining raw materials such as polyesters, adhesives, silicone, adhesive tapes, foams, plastics, felts, rubbers, liners and metals, as well as other materials, to create new products. Materials such as paper, plastic film, foil and cloth often are produced in long, continuous sheets that are rolled up for more convenient handling and transportation. These rolls of material vary significantly in size and weight — ranging from wide and weighing as much as several tons. The converting industry takes these continuous rolls of thin, flat materials — known as webs — threads them through processing machines (such as printing presses, laminating, coating and slitting machines) and converts or changes the web of material into an intermediate form or final product. For example, a converter’s equipment might take a web of plastic film, cut it into lengths, and fuse their edges, thus converting it into plastic bags.
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Polyurethane foam, close-up Otto Bayer and his coworkers at IG Farben in Leverkusen, Germany, first made polyurethanes in 1937. The new polymers had some advantages over existing plastics that were made by polymerizing olefins or by polycondensation, and were not covered by patents obtained by Wallace Carothers on polyesters. Early work focused on the production of fibres and flexible foams and PUs were applied on a limited scale as aircraft coating during World War II. Polyisocyanates became commercially available in 1952, and production of flexible polyurethane foam began in 1954 using toluene diisocyanate (TDI) and polyester polyols. These materials were also used to produce rigid foams, gum rubber, and elastomers. Linear fibers were produced from hexamethylene diisocyanate (HDI) and 1,4-Butanediol (BDO). In 1956 DuPont introduced polyether polyols, specifically poly(tetramethylene ether) glycol, and BASF and Dow Chemical started selling polyalkylene glycols in 1957.
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Lactones contribute significantly to the flavor of fruit, and of unfermented and fermented dairy products, and are therefore used as flavors and fragrances. Some examples are γ-decalactone (4-decanolide), which has a characteristic peach flavor; δ-decalactone (5-decanolide), which has a creamy coconut/peach flavour; γ-dodecalactone (4-dodecanolide), which also has a coconut/fruity flavor, a description which also fits γ-octalactone (4-octanolide), although it also has a herbaceous character; γ-nonalactone, which has an intense coconut flavor of this series, despite not occurring in coconut, and γ-undecalactone. Macrocyclic lactones (cyclopentadecanolide, 15-pentadec-11/12-enolide) have odors similar to macrocyclic ketones of animal origin (muscone, civetone), but they can be prepared more easily, for example, by depolymerization of the corresponding linear polyesters. Replacement of a methylene unit by oxygen barely affects the odor of these compounds, and oxalactones with 15 – 17-membered rings are produced in addition to cyclopentadecanolide (e. g.
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It also is used as an ingredient in flux coatings on welding rods, in some special greases, and as coatings for core and mold release compounds, facing agents, and mold washes in foundry applications. Dry-ground phlogopite mica is used in automotive brake linings and clutch plates to reduce noise and vibration (asbestos substitute); as sound-absorbing insulation for coatings and polymer systems; in reinforcing additives for polymers to increase strength and stiffness and to improve stability to heat, chemicals, and ultraviolet (UV) radiation; in heat shields and temperature insulation; in industrial coating additive to decrease the permeability of moisture and hydrocarbons; and in polar polymer formulations to increase the strength of epoxies, nylons, and polyesters. Mica flakes embedded in a fresco for glitter Wet-ground mica, which retains the brilliance of its cleavage faces, is used primarily in pearlescent paints by the automotive industry. Many metallic-looking pigments are composed of a substrate of mica coated with another mineral, usually titanium dioxide (TiO2).
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When Wallace Carothers arrived at DuPont in 1928 one of the tasks his group took on was the development of new synthetic fibers for textiles. At that time a number of natural polymers such as latex and cellulose were in common use, rayon as a semisynthetic from nitrated cellulose had recently been improved and begun upending the textile industries, and some fully synthetic polymers such as bakelite were also known and being used for certain applications, but the existing fully synthetic polymers could not be drawn into fibers and spun into thread, so great opportunity existed to manufacture thread and yarn from synthetic polymers to join or replace the existing fibers in the market (natural fibers such as cotton, wool, linen, and silk and artificial fiber in the various recently emerged types of rayon). The approach taken by Carothers' group was to adapt known syntheses that produced short-chain polymers to produce long-chain molecules. The first break was finding that bifunctional esterification could produce long molecule chains which today are known as aliphatic polyesters, but at that time were called superpolymers.
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Mulkidjanian and co-authors think that the marine environments did not provide the ionic balance and composition universally found in cells, as well as of ions required by essential proteins and ribozymes found in virtually all living organisms, especially with respect to K+/Na+ ratio, Mn2+, Zn2+ and phosphate concentrations. The only known environments that mimic the needed conditions on Earth are found in terrestrial hydrothermal pools fed by steam vents. Additionally, mineral deposits in these environments under an anoxic atmosphere would have suitable pH (as opposed to current pools in an oxygenated atmosphere), contain precipitates of sulfide minerals that block harmful UV radiation, have wetting/drying cycles that concentrate substrate solutions to concentrations amenable to spontaneous formation of polymers of nucleic acids, polyesters and depsipeptides, both by chemical reactions in the hydrothermal environment, as well as by exposure to UV light during transport from vents to adjacent pools. Their hypothesized pre-biotic environments are similar to the deep-oceanic vent environments most commonly hypothesized, but add additional components that help explain peculiarities found in reconstructions of the Last Universal Common Ancestor (LUCA) of all living organisms.
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